Fruit beers are NOT ipso facto sweet

Let's get to the point: real fruit beers will not necessarily be sweet. That's correct: beers fermented with fruit will not, ipso facto, be sweet beers.

Think about it. If fruit beers were by definition sweet, then wouldn't all wines, fermented with fruit, be sweet as well? When fruit is used in the fermenter, the yeast will consume those fruit sugars. That's with beer just as it is with wine.

If a fruit beer is sweet, chances are it really isn't a fruit beer at all. Rather, it probably is a flavored beer: extracts, syrups, or chemical essences of some sort have been added to it.

A beer fermented with real fruit often won't taste wholly like that fruit. It'll taste like fermented fruit. Not quite a tautology, that's a subtle but important distinction. Refer, again, to wine. A good wine is rarely described as tasting like grapes.

There are some fruits, such as cherries or raspberries, that do impart distinguishable flavor after fermentation. Other fruits, such as watermelon, blueberries, strawberries add only a slight, generic fruitiness. If a beer tastes like watermelon, it's a flavoring added to the beer; if a beer tastes like pumpkin, it's not the vegetable, it's 'pumpkin' spices.

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There is a common misconception that lambic beers, produced in Belgium, are, as a class, sweet and fruity beers.

Lambics, comprised of sizable amounts of wheat in their grists, are spontaneously fermented beers. As a result, they are suffused with acetic and lactic acids produced by native yeasts and bacteria.  Some lambics are indeed additionally fermented with fruit, commonly raspberries or cherries. But the fruit sugars in those ferment out fully - imparting more sourness and flavor - not sweetness.

That being said, yes, there are some sweet flavored gueuze-lambics. These have been sweetened after fermentation with fruit juice, and then pasteurized. These 'beer cocktails' are what many folk mistakenly refer to when they talk about lambics.

I recently read a complimentary piece on Clipper City Brewing's Oxford Raspberry Wheat on-line at Beer Advocate. Observing that the beer is not sweet, the article noted that the beer is not a lambic, but an American-style wheat beer. Real raspberries are added to the fermenter where they are consumed by the yeast. The beer has a wine-like finish but not the intense sourness of a lambic.

Oxford Raspberry Wheat has a long pedigree. Born in 1991 at the now defunct British Brewing Company (later renamed Oxford Brewing), it is the original and oldest fruit beer brand of the East Coast. When that brewery folded in 1998, Clipper City had already been contract-brewing the bottled version of the beer - true to the recipe. Clipper City continues with the same recipe today.

[UPDATE: Clipper City, now called Heavy Seas Brewing, discontinued its Oxford line of beers in 2009.]